distribution/registry/auth/silly/access.go
Cory Snider d0f5aa670b Move context package internal
Our context package predates the establishment of current best practices
regarding context usage and it shows. It encourages bad practices such
as using contexts to propagate non-request-scoped values like the
application version and using string-typed keys for context values. Move
the package internal to remove it from the API surface of
distribution/v3@v3.0.0 so we are free to iterate on it without being
constrained by compatibility.

Signed-off-by: Cory Snider <csnider@mirantis.com>
2023-10-27 10:58:37 -04:00

101 lines
2.8 KiB
Go

// Package silly provides a simple authentication scheme that checks for the
// existence of an Authorization header and issues access if is present and
// non-empty.
//
// This package is present as an example implementation of a minimal
// auth.AccessController and for testing. This is not suitable for any kind of
// production security.
package silly
import (
"context"
"fmt"
"net/http"
"strings"
"github.com/distribution/distribution/v3/internal/dcontext"
"github.com/distribution/distribution/v3/registry/auth"
)
// accessController provides a simple implementation of auth.AccessController
// that simply checks for a non-empty Authorization header. It is useful for
// demonstration and testing.
type accessController struct {
realm string
service string
}
var _ auth.AccessController = &accessController{}
func newAccessController(options map[string]interface{}) (auth.AccessController, error) {
realm, present := options["realm"]
if _, ok := realm.(string); !present || !ok {
return nil, fmt.Errorf(`"realm" must be set for silly access controller`)
}
service, present := options["service"]
if _, ok := service.(string); !present || !ok {
return nil, fmt.Errorf(`"service" must be set for silly access controller`)
}
return &accessController{realm: realm.(string), service: service.(string)}, nil
}
// Authorized simply checks for the existence of the authorization header,
// responding with a bearer challenge if it doesn't exist.
func (ac *accessController) Authorized(ctx context.Context, accessRecords ...auth.Access) (context.Context, error) {
req, err := dcontext.GetRequest(ctx)
if err != nil {
return nil, err
}
if req.Header.Get("Authorization") == "" {
challenge := challenge{
realm: ac.realm,
service: ac.service,
}
if len(accessRecords) > 0 {
var scopes []string
for _, access := range accessRecords {
scopes = append(scopes, fmt.Sprintf("%s:%s:%s", access.Type, access.Resource.Name, access.Action))
}
challenge.scope = strings.Join(scopes, " ")
}
return nil, &challenge
}
ctx = auth.WithUser(ctx, auth.UserInfo{Name: "silly"})
ctx = dcontext.WithLogger(ctx, dcontext.GetLogger(ctx, auth.UserNameKey, auth.UserKey))
return ctx, nil
}
type challenge struct {
realm string
service string
scope string
}
var _ auth.Challenge = challenge{}
// SetHeaders sets a simple bearer challenge on the response.
func (ch challenge) SetHeaders(r *http.Request, w http.ResponseWriter) {
header := fmt.Sprintf("Bearer realm=%q,service=%q", ch.realm, ch.service)
if ch.scope != "" {
header = fmt.Sprintf("%s,scope=%q", header, ch.scope)
}
w.Header().Set("WWW-Authenticate", header)
}
func (ch challenge) Error() string {
return fmt.Sprintf("silly authentication challenge: %#v", ch)
}
// init registers the silly auth backend.
func init() {
auth.Register("silly", auth.InitFunc(newAccessController))
}